This invention relates generally to freezeproof or freeze resistant valve assemblies for use in an outdoor drinking fountain or the like, to provide a reliable water supply particularly during cold weather conditions. More specifically, this invention relates to an improved freezeproof valve assembly designed for collecting residual water from fountain supply lines within an underground sump chamber where it is safeguarded against freezing, and for subsequently discharging the collected residual water to a main fountain drain.
Outdoor drinking fountains are generally known in the art and typically include a fountain or bubbler head mounted over a basin which is supported on a fountain pedestal at a selected height above the ground. A main on-off valve including a valve handle or actuator is normally mounted on or near the basin for convenient actuation to initiate water flow to the fountain head which produces a gentle stream projected upwardly over the basin for convenient drinking access. Excess water is collected within the basin and guided thereby to a main drain for flow to a suitable waste site, such as to a sewer line.
During cold winter weather conditions, outdoor drinking fountains have encountered freeze problems. More specifically, the fountain is typically coupled to a water supply line which is buried underground at a depth below the normal frost line to prevent water therein from freezing. However, the water supply line is connected to the fountain by a standpipe or the like which necessarily extends above the frost line and further above the ground to supply water to the fountain head. Water residing within the standpipe is exposed to freezing temperatures and thus may freeze therein to obstruct water flow and fountain usage, while additionally posing a significant risk of pipe breakage. In the past, this freeze problem has typically been addressed by draining the standpipe or the like and disabling the drinking fountain for the duration of the winter season.
More recently, freezeproof valve mechanisms have been developed for use in an outdoor drinking fountain or the like to permit continued fountain use during cold weather conditions without significant risk of pipe freeze-up or breakage. In such mechanisms, a valve actuator is typically provided on the fountain pedestal for operating the main on-off valve positioned remotely at an underground location below the frost line. When the main valve is turned on, water is allowed to flow upwardly through a standpipe to the fountain head for dispensing. However, when the main valve is turned off, residual water within the standpipe is drained away. In earlier designs, this residual water was discharged to the ground. In more current designs, this residual water has been drained to an underground collection chamber where it is temporarily stored below the frost line to prevent freezing thereof. In some arrangements, the collected water is mixed with supply water for flow to the fountain head the next time the fountain is turned on, as described in U.S. Pat. No. 4,282,895 and 4,520,836. Alternately, in another and more preferred design, the collected water is discharged to the main fountain drain the next time the fountain is turned on, as described in U.S. Pat. No. 5,553,637.
While these above-described freezeproof valve mechanisms function to permit fountain operation on a year-round basis, there still exists an ongoing need for further improvements, particularly with respect to eliminating undesirable failure modes. More specifically, in the freezeproof valve mechanism described in U.S. Pat. No. 5,553,637, water pressure within the underground water supply line is employed when the main valve is turned off to retract a spring-loaded piston within the collection chamber so that residual water in a fountain standpipe can drain to the collection chamber. When the main valve is turned on, the water pressure is substantially relieved from the piston which advances by spring action to expel the collected water through a discharge conduit to the fountain drain, followed by subsequent pressure responsive piston retraction when the main valve is again turned off to allow residual water within the standpipe and the discharge conduit to drain into the collection chamber. However, if the water supply pressure is interrupted for any reason, the piston will be spring-advanced prematurely and spring-retained in the advanced position, whereby the discharge conduit will be filled with water that is exposed to freezing temperature conditions.
The improved freezeproof valve assembly of the present invention overcomes these problems and disadvantages by providing an underground sump chamber with a piston movably mounted therein, wherein the piston has a normal unbiased retracted position to allow water to drain into the sump chamber when the main fountain valve is turned off, or when the water supply pressure is interrupted.